Background Drug-resistant tuberculosis (DR-TB) is one of the challenging forms of TB to treat, not only in adults but also in children and adolescents. Further, there is a void in the treatment strategy exclusively for children due to various reasons, including paucity of pharmacokinetic (PK) data on anti-TB drugs across the globe. In this context, the present study aimed at assessing the PK of some of the anti-TB drugs used in DR-TB treatment regimens.Method A multicentre observational study was conducted among DR-TB children and adolescents (n = 200) aged 1-18 years (median: 12 years; IQR: 9-14) treated under programmatic settings in India. Steady-state PK (intensive: n = 89; and sparse: n = 111) evaluation of moxifloxacin, levofloxacin, cycloserine, ethionamide, rifampicin, isoniazid and pyrazinamide was carried out by measuring plasma levels using HPLC methods.Results In the study population, the frequency of achieving peak plasma concentrations ranged between 13% (for rifampicin) to 82% (for pyrazinamide), whereas the frequency of suboptimal peak concentration for pyrazinamide, cycloserine, moxifloxacin, levofloxacin and rifampicin was 15%, 19%, 29%, 41% and 74%, respectively. Further, the frequency of supratherapeutic levels among patients varied between 3% for pyrazinamide and 60% for isoniazid. In the below-12 years age category, the median plasma maximum concentration and 12 h exposure of moxifloxacin were significantly lower than that of the above-12 years category despite similar weight-adjusted dosing.Conclusions Age significantly impacted the plasma concentration and exposure of moxifloxacin. The observed frequencies of suboptimal and supratherapeutic concentrations underscore the necessity for dose optimization and therapeutic drug monitoring in children and adolescents undergoing DR-TB treatment.
The current treatment protocol for drug-sensitive tuberculosis involves all four first-line anti-tuberculosis drugs: rifampicin, isoniazid, pyrazinamide and ethambutol hydrochloride in a single tablet, known as fixed-dose combination tablets. However, the analytical methods are scanty to test all these drugs simultaneously in a single run without any pre-sample process or using a simple method suitable for resource-limited settings. In this method, 50 mM potassium phosphate buffer containing 0.2% triethylamine (without pH adjustment) added with acetonitrile (98:2, v/v) was served as mobile phase A, while mobile phase B was 100% acetonitrile. All four drugs were separated within 10.3 min using a gradient mobile phase program in a C18 column (150 mm x 4.6 mm; 5 mu m) and detected at two ultraviolet wavelengths (238 nm for rifampicin, isoniazid and pyrazinamide, and 210 nm for ethambutol hydrochloride). The method was selective, sensitive and linear with a correlation coefficient >0.999 with the acceptable precision and accuracy (<2% relative standard deviation) for all four drugs. In conclusion, the method is simple and it does not require any pH adjustment of the buffer/mobile phase, and within 11 min, the separation of all four drugs can be achieved. Overall, the method is suitable for quality testing of fixed-dose combination tablets in limited-resource settings.
Purpose: Pharmacokinetic (PK) studies are critical for dose optimization, and there is a paucity of linezolid (LZD) PK data for prolonged use in drug-resistant tuberculosis (DR-TB). Therefore, the authors evaluated the pharmacokinetics of LZD at two-time intervals in DR-TB during long-term use. Methods: PK evaluation of LZD was performed at the end of the 8th and 16th weeks of treatment in a randomly selected subset of adult pre-extensively drug-resistant pulmonary tuberculosis patients (n = 18) from a multicentric interventional study (Building Evidence to Advance Treatment of TB/BEAT study; CTRI/2019/01/017310), wherein a daily dose of 600 mg LZD was used for 24 weeks. Plasma LZD levels were measured using a validated high-pressure liquid chromatography (HPLC) method. Results: The LZD median plasma C max was comparable between the 8th and 16th weeks [18.3 mg/L, interquartile range (IQR: 15.5–20.8 and 18.8 mg/L, IQR: 16.0–22.7, respectively)]. However, the trough concentration increased significantly in the 16th week (3.16 mg/L, IQR: 2.30–4.76), compared with the 8th week (1.98 mg/L, IQR: 0.93–2.75). Furthermore, compared with the 8th week, in the 16th week, there was a significant increase in drug exposure (AUC 0-24 = 184.2 mg*h/L, IQR: 156.4–215.8 versus 233.2 mg*h/L, IQR: 187.9–277.2), which corroborated with a longer elimination half-life (6.94 hours, IQR: 5.55–7.99 versus 8.47 hours, IQR:7.36–11.35) and decreased clearance (2.91 L/h, IQR: 2.45–3.33 versus 2.19 L/h, IQR: 1.49–2.78). Conclusions: Long-term daily intake of 600 mg LZD resulted in a significant elevation in trough concentration (>2.0 mg/L) in 83% of the study participants. Furthermore, increased LZD drug exposure may be partly because of decreased clearance and elimination. Overall, the PK data underscore the need for dose adjustment when LZDs are intended for long-term treatment.
Non-alcoholic fatty liver disease (NAFLD) is a progressive disease and one of the leading causes of death. An unnamed disease has become a global epidemic disease of public health concern. This spectrum of diseases manifests itself with initial accumulation of excessive triglycerides (due to de novo lipogenesis) in the hepatocytes, leading to simple steatosis. Although its aetiology is multi-factorial, lifestyle changes (diet and physical activity) are considered to be the key thriving factors. In this context, high fructose consumption is associated with an increased risk for developing NAFLD in humans, while high-fructose feeding to experimental animals results in hepatic steatosis and non-alcoholic steatohepatitis, by increasing hepatic lipogenesis. Among several lipogenic genes, the endoplasmic reticulum-bound stearoyl-CoA desaturase 1 (SCD1) is the key determinant of triglycerides biosynthesis pathway, by providing monounsaturated fatty acids, through the incorporation of a double bond at the delta-9 position of saturated fatty acids, specifically, palmitic (C16: 0) and stearic (C18: 0) acids, yielding palmitoleic (C16:1) and oleic (C18: 1) acids, respectively. Various experimental studies involving SCD1 gene knockout and diet-induced rodent models have demonstrated that SCD1 plays a key role in the development of NAFLD, by modulating hepatic lipogenesis and thus triglyceride accumulation in the liver. Several pharmacological and dietary intervention studies have shown the benefits of inhibiting hepatic SCD1 in the pathogenesis of NAFLD. In this review, we give an overview of SCD1 in NAFLD, based on the current experimental evidence and the translational applicability of SCD1 inhibition in human NAFLD conditions, besides discussing the limitations and way-forward.
ABSTRACT Vitamin A deficiency and excessive fructose consumption are known to cause functional impairment of various vital organs including the brain in the mammalian system. However, the underlying pathways and molecular mechanisms are not fully understood. Objective Here, we assessed the impact of vitamin A deficiency (both alone and in combination with fructose) on the retinol status, phospholipids fatty acid composition and pathways associated with the endoplasmic reticulum (ER) stress and energy homeostasis of the brain. For this purpose, weanling male Wistar rats were divided into four groups consisting of 8 rats each, except 16 for the second group and they received one of the following diets; control, vitamin A-deficient (VAD), high fructose (HFr) and HFr with VAD for 16 weeks, except half of the VAD diet-fed rats, were shifted to HFr diet, after 8 weeks period. Results The retinol content of the whole brain remained comparable across the groups, despite a significant reduction in the plasma at the end of VAD diet feeding. However, it suppressed the HFr-induced neuropeptide Y and agouti-related peptide, while rescuing the leptin receptor mRNA. Among ER stress markers, CCAAT/Enhancer-binding protein homologues protein levels were elevated significantly in the VAD diet-fed group. Further, the long-chain polyunsaturated fatty acid levels showed an increase in the brain phospholipids across the experimental groups, compared to that of the control. Conclusion Vitamin A deficiency causes ER stress in the brain, and retinol seems to play a regulatory role in the fructose-mediated transcriptional regulation of the genes involved in energy homeostasis.
Inflammation is one of the primary factors associated with the causation and/or progression of several lifestyle disorders, including obesity, type 2 diabetes and non-alcoholic fatty liver disease (NAFLD). NAFLD is a spectrum of disorders, and starts with simple steatosis, progresses to non-alcoholic steatohepatitis, and then advances to fibrosis, cirrhosis and finally, hepatocellular carcinoma, due to perpetual cycles of insults caused by inflammation and other cellular stress. Emerging evidence has documented that patients with NAFLD have severe coronavirus disease 2019 (COVID-19), and patients with COVID-19 have a higher liver injury and mortality. Although the exact cause or mechanism is not known, inflammatory cytokine storm is a characteristic feature of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and is known to be associated with higher mortality among COVID-19 patients. Therefore, the COVID-19 pandemic seems to be a major concern in NAFLD patients, who have contracted SARS-CoV-2 infection and develop COVID-19. This is evident in patients at any stage of the NAFLD spectrum, as the inflammatory cytokine storm may cause and/or aggravate the progression or severity of NAFLD. Thus, there is a need for resolution of the inflammatory cytokine storm in these patients. A large body of evidence has demonstrated the efficacy of omega-3 long-chain polyunsaturated fatty acids (ω-3 LCPUFA) in NAFLD conditions, due to their anti-inflammatory, immunomodulatory and anti-viral properties. Therefore, intervention with ω-3 LCPUFA, an effective pharmaconutrient along with the standard treatment for COVID-19 may be useful in the management of the NAFLD spectrum in COVID-19 patients with pre-existing NAFLD conditions by resolving the inflammatory cytokine storm and thereby attenuating its progression. Although there are challenges in implementation, optimistically they can be circumvented and the pharmaconutrition strategy may be potentially helpful in tackling both the pandemics; NAFLD and COVID-19 at least in this subset of patients.
Nutritional intervention is a key strategy in the control and management of non-communicable diseases. Here, initially, we evaluated the effects of carrot juice (CJ) on some of the physical and biochemical parameters in rats fed with high-fructose diet, then in type 2 diabetic subjects. For the animal study, weanling male Wistar rats were given control (n = 6) or high fructose (HFr; n = 24) diet for 8 weeks. Then, the HFr group rats were subdivided into 4 groups (n = 6 in each) and continued either on HFr diet or shifted to control diet, with or without CJ (0.3 mg β-carotene) ingestion orally for 8 weeks. At the end, the ingestion of CJ reversed the HFr-induced adiposity (23 ± 1.6 vs 18 ± 1.1, P = .038), hypertriglyceridemia (182 ± 18.2 vs 90 ± 10.5 mg/dL, P <0.001), and hyperinsulinemia (81 ± 14.7 vs 40 ± 7.5 µU/mL, P = .014), while increased the retinol levels in liver (240 ± 38.4 vs 492 ± 61.2 µg/g, P = .002) and adipose tissue (1.8 ± 0.09 vs 2.5 ± 0.18 µg/g, P = .026). On the other hand, in the diabetic subjects (7 males and females each, n = 14) compared to their baseline, the daily consumption of 50 mL CJ (~2400 µg β-carotene) for 6 weeks significantly reduced the body weight (69.4 ± 4.13 vs 69.0 ± 4.09 kg, P = .014), BMI (27.4 ± 1.07 vs 27.2 ± 1.06 kg/m 2 , P = .007), and fat% (33.4 ± 1.87 vs 31.9 ± 2.13, P = .029) with an increase in plasma β-carotene levels (0.21 ± 0.045 vs 0.45 ± 0.089 µmol/L, P = .044). Although CJ increased the glucose (145 ± 10.4 vs 165 ± 11.4 mg/dL, P = .039), insulin, and glycated hemoglobin levels remained unaltered. In conclusion, the consumption of carrot juice reversed the HFr-induced metabolic abnormalities in a rat model and decreased body weight and BMI of diabetic subjects.
The liver plays a crucial role in endogenous metabolic activity and homeostasis of macro and micronutrients. Further, it acts as a metabolic hub in mammals, where the ingested food-derived nutrients and xenobiotics or drugs are metabolized for utilization and/or excretion through its enzymatic and non-enzymatic machinery. Nutritional deficiency, one of the major public health problems, is associated with global disease burden, including pulmonary tuberculosis (PTB) caused by Mycobacterium tuberculosis (Mtb) infection. Though it is a curable and preventable infectious disease, millions of people succumb to death, and people in numbers larger than this are still suffering. This scenario is further complicated by the addition of new cases, disease recurrence, and the emergence of drug-resistant, all of which contribute to the spread of this epidemic. Though the manifestation of TB disease has multiple aetiologies, poor nutritional status and sub-optimal therapeutic concentrations of first-line anti-TB drugs are considered as potential contributors to its widespread prevalence. Among various factors, the pharmacokinetic variability of anti-TB drugs is one of the main causes for sub-optimal therapeutic drug concentration in TB patients, which is influenced by the host's genetic make-up and nutritional status, besides several others. However, the role of epigenetic changes in hepatic drug metabolic pathways and their transcript levels is largely unexplored. Therefore, in this review, an attempt has been made to understand the role of micronutrient deficiencies with special reference to fat-soluble vitamins, namely vitamin A, D, & E in pulmonary TB, their possible impact on epigenetic changes on the drug-metabolizing pathway genes, thus their expression levels and plausible influence on pharmacokinetic variability of anti-TB drugs, besides discussing the limitations and emerging potential opportunities. Eventually, this would help in developing the host-directed/personalized therapeutic strategies for the elimination of pulmonary tuberculosis (PTB).
The role of sexual dimorphic adipose tissue fat accumulation in the development of insulin resistance is well known. However, whether vitamin A status and/or its metabolic pathway display any sex- or depot (visceral/ subcutaneous)-specific pattern and have a role in sexual dimorphic adipose tissue development and insulin resistance are not completely understood. Therefore, to assess this, 5 weeks old Wistar male and female rats of eight from each sex were provided either control or diabetogenic (high fat, high sucrose) diet for 26 weeks. At the end, consumption of diabetogenic diet increased the visceral fat depots (p < 0.001) in the males and subcutaneous depot (p < 0.05) in the female rats, compared to their sex-matched controls. On the other hand, it caused adipocyte hypertrophy (p < 0.05) of visceral depot (retroperitoneal) in the females and subcutaneous depot of the male rats. Although vitamin A levels displayed sex- and depot-specific increase due to the consumption of diabetogenic diet, the expression of most of its metabolic pathway genes in adipose depots remained unaltered. However, the mRNA levels of some of lipid droplet proteins (perilipins) and adipose tissue secretory proteins (interleukins, lipocalin-2) did display sexual dimorphism. Nonetheless, the long-term feeding of diabetogenic diet impaired the insulin sensitivity, thus affected glucose clearance rate and muscle glucose-uptake in both the sexes of rats. In conclusion, the chronic consumption of diabetogenic diet caused insulin resistance in the male and female rats, but did not corroborate with sexual dimorphic adipose tissue fat accumulation or its vitamin A status.
The liver is the main site of lipid metabolism and vitamin A storage. Dietary factors are known to affect liver function, thereby leading to metabolic abnormalities. Here, we assessed the impact of long-term feeding of a high-fat diet on hepatic vitamin A status and lipid metabolism. For this purpose, 14 male and 14 female 35-day-old mice (strain C57BL/6J) were each divided into 2 groups of 7 animals and fed either a stock diet or a high-fat (HF) diet for 26 weeks. In addition to increased body weight/weight gain, the HF diet induced hypertriglyceridemia in both (p < 0.01). However, liver triglyceride levels were comparable among groups, which could be partly explained by unaltered expression of various lipogenic pathway proteins such as sterol regulatory element binding protein 1 (SREBP1), fatty acid synthase (FAS), microsomal triglyceride transfer protein (MTTP), and glycerol 3-phosphate acyl transferase (GPAT). On the other hand, hepatic retinol stores increased significantly in both sexes, whereas males displayed elevated circulatory retinol levels. Notably, long-term feeding of a HF diet elevated n-3 polyunsaturated fatty acid (PUFA) and docosahexaenoic acid (DHA, C22:6) levels in the liver (p <= 0.001), which is in line with the over-expression of very long-chain fatty acid elongase 2 (ELOVL2) protein in both sexes of mice (p < 0.01). In conclusion, very long-term feeding of a HF diet increased hepatic retinol stores and induced hypertriglyceridemia. However, it had no effect on hepatic triglyceride accumulation, possibly due to increased DHA levels arising from the ELOVL2-mediated elongation pathway.
Background/Objective: To determine the glycemic index (GI) of RNR15048 rice variety and study its effectiveness in reducing postprandial blood glucose levels and the regulation of lipid profile in patients with type 2 diabetes. Subjects/Methods: The GI of RNR15048 rice was measured in 54 healthy subjects in the age group of 30-50 years. The dietary intervention study was conducted in 80 subjects with diabetes in the age group of 40-60 years where 40 test subjects replaced their regular rice with RNR 15048 rice variety for 3 months. Anthropometric and biochemical parameters, HbA1c, fasting blood glucose, lipid profile, insulin were determined before and after the study. Results: The glycemic index (GI) of RNR 15048 rice variety was observed to be low with GI of 51.72 ± 3.39. The dietary intervention study in type 2 diabetic subjects revealed significant decrease in fasting blood glucose (158.4 ± 9.30 vs 140.2 ± 8.87 mg/dL) and HbA1c levels (7.1 ± 0.34 vs 6.1 ± 0.33 %) with an increase in HDL levels (33.7 ± 1.29 vs 37.1 ± 1.83 mg/dL) while parameters such as body weight, blood pressure and insulin levels did not show any significant changes. Conclusion: Low GI rice is effective in the reduction of postprandial glucose response in type 2 diabetes and increase in plasma HDL levels and therefore useful in the management of type 2 diabetes and in the long term management of cardiovascular diseases.
Background & objectives: Stearoyl-CoA desaturase 1 (SCD1) is a key lipogenic enzyme responsible for endogenous synthesis of monounsaturated fatty acids (MUFA) and plays a key role in various pathophysiology, including fatty liver diseases. In this experimental study the impact of vitamin A deficiency was assessed on SCD1 regulation in relation to kidney biology, under high fructose (HFr) diet-fed condition in rats. Methods: Forty male weanling (21 day old) Wistar rats were divided into four groups control, vitamin A-deficient (VAD), HFr, VAD with HFr consisting of eight rats each, except 16 for the VAD group. The groups received one of the following diets: control, VAD, HFr and VAD with HFr for 16 wk, except half of the VAD diet-fed rats were shifted to HFr diet, after eight week period. Results: Feeding of VAD diet (alone or with HFr) significantly reduced the kidney retinol (0.51, 0.44 μg/g vs. 2.1 μg/g; P < 0.05), while increased oleic (C18:1) and total MUFA levels (23.3, 22.2% and 27.3, 25.4% respectively vs. 14.7 and 16.6%; P < 0.05) without affecting the SCD1, both at protein and mRNA levels, when compared with HFr. Comparable, immunohistological staining for SCD1 was observed in the distal convoluted tubules. Despite an increase in MUFA, morphology, triglyceride content and markers of kidney function were not affected by VAD diet feeding. Interpretation & conclusions: Feeding of VAD diet either alone or under HFr condition increased the kidney oleic acid (C18:1) levels and thus total MUFA, which corroborated with elevated SCD1 activity index, without affecting its expression status. However, these changes did not alter the kidney morphology and function. Thus, nutrient-gene regulation in kidney biology seems to be divergent.
Nonalcoholic fatty liver disease (NAFLD) is one of the leading causes of liver-associated mortality. It is a spectrum of disorders, initiated by hepatic triglyceride accumulation, which progresses to nonalcoholic steatohepatitis and advances to various stages and, finally, hepatocellular carcinoma, due to multiple biological insults. Although the etiology is multifactorial, altered lifestyle is associated with increased incidence of NAFLD. Therefore, the management of NAFLD through lifestyle intervention is preferred to the use of pharmacological agents (although no specific drug is available till date). Among a few, dietary intervention for NAFLD by n-3 polyunsaturated fatty acid (PUFA) is found to be promising. Furthermore, the advent of lipidomics has identified many newer lipid molecules, including bioactive lipid mediators, particularly from n-3 PUFA, and they exhibit the resolution of inflammatory process and antiinflammatory action. In this chapter, we give an overview of NAFLD, its prevalence and causation, and provide the detailed literature review of n-3 PUFA supplementation on human NAFLD, its lipid mediators, and their role in disease progression.
Here, we tested a hypothesis that vitamin A and/or its metabolic pathways are involved in the high-fructose-mediated alteration in adipose tissue biology. For this purpose, weanling male Wistar rats were provided with one of the following diets: control (C), control with vitamin A deficiency (C-VAD), high fructose (HFr), and HFr with VAD (HFr-VAD) for 16 weeks, except that half of the C-VAD diet-fed rats were shifted to HFr diet (C-VAD(s)HFr), after 8-week period. Compared with control, feeding of HFr diet significantly increased the triglyceride content (P <= .01) and thus adipocyte size (hypertrophy) (P <= .001) in visceral adipose depot; retroperitoneal white adipose tissue (RPWAT) and these changes were corroborated with de novo lipogenesis, as evidenced by the increased glycerol-3-phosphate dehydrogenase activity (P <= .01) and up-regulation of lipogenic pathway transcripts, fructose transporter, and aldehyde dehydrogenase 1 A1. On the contrary, the absence of vitamin A in the HFr diet (HFr-VAD) failed to exert these changes; however, it induced adipocyte hyperplasia. Further, vitamin A deficiency-mediated changes were reversed by replenishment, as evident from the group that was shifted from C-VAD to HFr diet. In conclusion, vitamin A and its metabolic pathway play a key determinant role in the high-fructose-induced triglyceride accumulation and adipocyte hypertrophy of visceral white adipose depot. Significance of the study Here, we report the metabolic impact of high-fructose feeding under vitamin A-sufficient and vitamin A-deficient conditions. Feeding of high-fructose diet induced triglyceride accumulation and adipocyte hypertrophy of the visceral white adipose depots. These changes corroborated with augmented expression of vitamin A and lipid metabolic pathway genes. Contrarily, absence of vitamin A in the high-fructose diet did not elicit such responses, while vitamin A replenishment reversed the changes exerted by vitamin A deficiency. To our knowledge, this is the first study to report the role of vitamin A and its metabolic pathway in the high-fructose-induced triglyceride synthesis and its accumulation in visceral adipose depot and thus provide a new insight and scope to understand these nutrients interaction in clinical conditions.
Previously, we reported that vitamin A deficiency resulted in the reduction of stearoyl-CoA desaturase 1 (SCD1) and monounsaturated fatty acid (MUFA) levels, which corroborated with attenuation of high fructose-induced hepatic steatosis. Here, we aimed at assessing the effect of vitamin A deficiency on SCD1, MUFA levels and their impact on pancreas’ structure and functions. Male weanling Wistar rats fed one of the four diets, namely control (Con), vitamin A-deficient (VAD), highfructose (HFr) and vitamin A-deficient diet with highfructose (VADHFr) for 16 weeks period. Compared to the control, feeding of VAD diet (alone or with HFr) resulted in pancreatic intra-islet vessel dilation and reduced plasma insulin, glucagon and C-peptide levels, however, glucose levels decreased only in VADHFr group. In line with plasma levels, VAD diet-fed animals displayed lower immunostaining for insulin and glucagon, which corroborated with increased apoptotic staining observed in the islet regions, possibly due to increased cellular stress, as indicated by high immunostaining for endothelial nitric oxide synthase (eNOS) and CCAAT/Enhancer-binding protein homologues protein (CHOP). On the other hand, it significantly decreased the SCD1 protein, which corroborated with reduced MUFA levels, particularly, oleic acid (C18:1), when compared to the control and HFr groups. In conclusion, chronic vitamin A deficiency altered the structure and functions of pancreas by diminishing the islet cells, possibly by inducing cellular stress-mediated apoptosis and decreasing SCD1-mediated oleic acid (C18:1) synthesis. Thus, the data suggest that unlike liver, the reduction in SCD1 and MUFA levels in the pancreas exerts deleterious effects on its functions and perturb the overall cellular metabolism.
Development of low glycemic-foods is important in the prevention and management of type 2 diabetes. In this context, we prepared four test foods (TFs) (two mixed mini-meals and two breakfast items) with low glycemic-components and assessed their glycemic index (GI) in young healthy non-diabetic volunteers with mean age of 29 yr, body mass index of 24 kg/m2, and fasting plasma glucose levels less than 4.62 mmol/L. Volunteers were given 50 g of glucose, as a reference food (RF) on the first day, and TFs, i.e. TF1 (mixed mini meal: roti made of wheat flour and chana dal+ curd), TF2 [mixed mini meal made of wheat, pearl barley, and Bengal gram flour (besan) mix with chana whole (unhusked chana+curd)], TF3 (pearl barley rawa upma), and TF4 (wheat rawa upma) were given 2-day intervals in the same order. Glucose levels at fasting conditions and after the consumption of RF and TFs at different time intervals (15, 30, 45, 60, 90, and 120 min) were measured, and the incremental area under curve (IAUC) for glucose and GI of the TFs were calculated. The glucose IAUC values at different time points were highest for TF2 (GI=71.9±7.4), while all other TFs had comparable GI in the range of 53.7~54.9. Among the various TFs, TF1, TF3, and TF4 exerted low to moderate glycemic response, and thus can be classified as low glycemic-foods. Nevertheless, these foods need to be tested for their efficacy in controlling and/or managing hyperglycemia and glucose over-load in diabetic subjects.
Brassica juncea, the Indian mustard variety has high erucic acid (22:1 n-9) in its oil, which causes several deleterious effects. The Centre for Genetic Manipulation of Crop Plants (India) has developed a zero-erucic and high-oleic acid transgenic mustard variety having 67% oleic acid, which is almost equivalent to that of olive oil, i.e. 71%. Therefore, we assessed its impact on erythrocyte osmotic fragility, fluidity and activities of membrane-bound enzymes and insulin sensitivity. 40 male Syrian golden hamsters of 6–8 weeks age, were divided into five groups, consisting of 8 hamsters in each and fed diet containing any one of the oils, i.e. groundnut (GNO), conventional mustard (OCM), low-erucic mustard (OLM), zero-erucic high-oleic transgenic mustard (OTM) and olive (OLO) at 10% level for 16 weeks. At the end, compared to OLO group, OTM-fed hamsters resisted osmotic shock-induced erythrocyte-haemolysis, which corroborated with higher docosahexaenoic acid (DHA; 22:6 n-3) levels in their erythrocyte membranes. However, it did affect neither the fluidity nor the activities of membrane-bound enzymes. Although fasting plasma glucose, insulin and free fatty acid levels were comparable among the various groups; during glucose challenge, OTM diet-fed animals displayed higher disposal rate of circulatory glucose, without altering the insulin levels, when compared to the conventional mustard; OCM. In conclusion, the consumption of oil from zero-erucic high-oleic transgenic mustard improved the DHA content of erythrocyte membrane, which possibly resisted haemolysis and enhanced glucose clearance during glucose overload. However, it did not affect the activities of erythrocyte membrane-bound enzymes and fluidity compared to olive oil.
Vitamin A and its metabolites modulate insulin resistance and regulate stearoyl-CoA desaturase 1 (SCD1), which are also known to affect insulin resistance. Here, we tested, whether vitamin A-mediated changes in insulin resistance markers are associated with SCD1 regulation or not. For this purpose, 30-week old male lean and glucose-intolerant obese rats of WNIN/GR-Ob strain were given either a stock or vitamin A-enriched diet, i.e. 2.6 mg or 129 mg vitamin A/kg diet, for 14 weeks. Compared to the stock diet, vitamin A-enriched diet feeding improved hyperglycemia and glucose-clearance rate in obese rats and no such changes were seen in lean rats receiving identical diets. These changes were corroborated with concomitant increase in circulatory insulin and glycogen levels of liver and muscle (whose insulin signaling pathway genes were up-regulated) in obese rats. Further, the observed increase in muscle glycogen content in these obese rats could be explained by increased levels of the active form of glycogen synthase, the key regulator of glycogen synthesis pathway, possibly inactivated through increased phosphorylation of its upstream inhibitor, glycogen synthase kinase. However, the unaltered hepatic SCD1 protein expression (despite decreased mRNA level) and increased muscle-SCD1 expression (both at gene and protein levels) suggest that vitamin A-mediated changes on glucose metabolism are not associated with SCD1 regulation. Chronic consumption of vitamin A-enriched diet improved hyperglycemia and glucose-intolerance, possibly, through the regulation of intracellular signaling and glycogen synthesis pathways of muscle and liver, but not associated with SCD1.
Here, we present the expression data on various metabolic pathways of liver with special emphasize on lipid and carbohydrate metabolism and long chain polyunsaturated fatty acid (PUFA) synthesis, both at gene and protein levels. The data were obtained to understand the effect of vitamin A deficiency on the expression status (both gene and protein levels) of some of the key factors involved in lipogenesis, fatty acid oxidation, triglyceride secretion, long chain PUFA, resolvin D1 synthesis, glucose transport and glycogen synthesis of liver, using modern biology tools, such as quantitative real-time PCR (RT-PCR) and immunoblotting techniques. This data article provides the supporting evidence to the article “Vitamin A deficiency suppresses high fructose-induced triglyceride synthesis and elevates resolvin D1 levels” [1] and therefore, these data may be referred back, for comprehensive understanding and interpretations and for future studies.
Background/Aims: Vitamin A and its metabolites are known to regulate lipid metabolism. However so far, no study has assessed, whether vitamin A deficiency per se aggravates or attenuates the development of nonalcoholic fatty liver disease (NAFLD). Therefore, here, we tested the impact of vitamin A deficiency on the development of NAFLD.Methods: Male weanling Wistar rats were fed one of the following diets; control, vitamin A-deficient (VAD), high fructose (HFr) and VAD with HFr (VADHFr) of AIN93G composition, for 16 weeks, except half of the VAD diet-fed rats were shifted to HFr diet (VAD(s)HFr), at the end of 8th week.Results: Animals fed on VAD diet with HFr displayed hypotriglyceridemia (33.5 mg/dL) with attenuated hepatic triglyceride accumulation (8.2 mg/g), compared with HFr diet (89.5 mg/dL and 20.6 mg/g respectively). These changes could be partly explained by the decreased activity of glycerol 3-phosphate dehydrogenase (GPDH) and the down-regulation of stearoyl CoA desaturase 1 (SCD1), both at gene and protein levels, the key determinants of triglyceride biosynthesis. On the other hand, n-3 long chain polyunsaturated fatty acid, docosahexaenoic acid and its active metabolite; resolvin D1 (RvD1) levels were elevated in the liver and plasma of VAD diet-fed groups, which was negatively associated with triglyceride levels. All these factors confer vitamin A deficiency mediated protection against the development of hepatic steatosis, which was also evident from the group shifted from VAD to HFr diet.Conclusions: Vitamin A deficiency attenuates high fructose-induced hepatic steatosis, by regulating triglyceride synthesis, possibly through GPDH, SCD1 and RvD1. (C) 2015 Elsevier B.V. All rights reserved.